Problem oriented specific purpose high level languages are called fourth generation Languages. They are less efficient languages as compared to fourth generation languages.so, they are less user friendly languages. They are mostly CUI (Character User Interface) based languages.Mostly, they are general purpose languages, so they cannot solve complex and specific types of real-world problems.Program must be translated into machine code.So, the translation process may take extra time.Most of the third generation languages are general purpose therefore they are not considered as efficient and reliable programming languages than fourth generation programming languages. The translation is performed by a language translator program such as interpreter or compiler. The translation process may take some extra processing time. BASIC program to calculate area of rectangleĮven though the high level languages have a number of significance, the instructions must be translated into machine language before execution. The third statement defines a new variable AREA and it stores the product and finally prints the output on screen. The first two statements of the program store the values 5 and 6 into the variables L and B respectively. For example, consider a BASIC program to calculate the area of a rectangle in figure below. They are also known as procedural languages because the instructions of language are written in step by step sequence of procedures. Examples of third generation languages are: FORTRAN, BASIC, Pascal, C, etc. Mostly, they are general purpose and machine independent languages. Third generation language is general purpose high level language in which the instructions are expressed in more like English structure and mathematical expressions So, it is a more efficient and powerful language for solving hardware interfacing programs. Assembly language allows programmers to interact directly with the hardware. Moreover, assembler automatically traces the errors in assembly program codes and gives messages about the causes of errors. The translation is done by a special translation program called assembler. A translator program must translate the assembly codes into equivalent machine codes before execution. The set of original program instructions is known as source code. Assembly language instruction format OPCODE ADD is a keyword for addition, A and B are common register variables in the processor and comment has no effect in the program. The general format of assembly language instructions is shown in the following example. It consists of sets of instructions composed with 0s and 1s that represent electrically off state and on state Machine Language pectively in computer systems.Īssembly language is a special type of low level language which consists of a set of alphanumeric instructions, called mnemonics. In the early days of computing, there was no complex hardware and software, so machine language was used for data input/output and process. Machine language is the first language of a computer system. The following figure shows the classification of programming languages. Third generation, fourth generation and fifth generation languages belong to this category. The instructions used in the high level language are very close to the English like structure and mathematical expression. Machine language and Assembly language belong to this category. Low level languages are closer to the languages that the computer internally uses itself. Programming languages are classified into two categories: high level languages (HLL) and low level languages (LLL). 5.1.2 Low level, High level, 4 GL programming Languages (Types of Programming Languages) General purpose programming languages are used for solving almost all types of problems and the specific purpose programming languages are used for solving problems of specific nature. Based on the nature of languages, they are classified into two categories: general purpose and specific purpose. Programming languages are classified into various ways. But, commercially only few of them are popular because of their simplicity, efficiency and compatibility to computer systems. Hundreds of programming languages have been developed in the last fifty years. Programming language is defined as a set of rules that provides a platform for instructing computers to perform some specific tasks.